How should my girlfriend care for her tattoo?

My girlfriend got a tattoo I think about a week or so ago. It's on her upper right back area, and it says "Jesus Lives" in cursive writing. Around a few of the letters (mainly the "i" and "v" in "lives") are some redness, which I believe is a sign of it starting to get infected. I got a tattoo when I was 13 on my upper right arm, and it started to get infected. I remember it was only starting to get infected before my sister took it over and did her magic on it (she has 15+ tattoos), but I don't remember what I did when she wasn't around to care for it. I'm nearly nineteen now, so it was about five years ago. I have a few questions on how to care for it.

1. What are the signs of a tattoo that is healing properly?
2. Is there anything I can do to help her, besides put the neosporin on her back where it is?
3. Is it okay to peel at it when it gets all crusty and stuff, or should I just leave it?
4. She said it itches a lot, and I keep rubbing it instead, so her skin doesn't get damaged, is this okay?
5. Is hemp lotion good for tattoos?

*Note: It's not that serious to the point where she needs a doctor, please don't suggest that.

Any other advice would be greatly appreciated.
Thanks so much, Y!A community.